Effects of citrus and avocado irrigation and nitrogen-form soil amendment on host selection by adult Homalodisca vitripennis (Hemiptera: Cicadellidae).

Host plant water status is thought to influence dispersal of the xylophagous leafhopper Homalodisca vitripennis Germar, especially where plants are grown under high evaporative demand. Preference by adult H. vitripennis for plants grown under different water deficit and nitrogen form fertilization regimens was studied under laboratory conditions. Leafhopper abundance and ovipositional preference were studied on potted 'Washington navel' orange and 'Haas' avocado in cage choice tests, and feeding rate was estimated using excreta produced by insects confined on plants. A similar study compared responses to citrus treated with 1:1 and 26:1 ratios of fertigated nitrate-N to ammonium-N. The insects were more abundant, oviposited, and fed significantly more on surplus-irrigated plants than on plants under moderate continuous deficit irrigation except avocado feeding, which was nearly significant. Plants exposed to drought became less preferred after 3 and 7 d in avocado and citrus, respectively. Citrus xylem fluid tension at this point was estimated at 0.93 MPa. A corresponding pattern of decline in feeding rate was observed on citrus, but on avocado, feeding rate was low overall and not statistically different between treatments. No statistical differences in abundance, oviposition, or feeding were detected on citrus fertigated with 26:1 or 1:1 ratios of nitrate-N to ammonium-N. Feeding occurred diurnally on both plant species. Discussion is provided on the potential deployment of regulated deficit irrigation to manage H. vitripennis movement as part of a multitactic effort to minimize the risk of disease outbreaks from Xylella fastidiosa Wells et al. in southern California agriculture.

Familial occurrence of Summitt syndrome or a variant example of Carpenter syndrome?

In this report, we describe three sibs presenting an identical malformation syndrome i.e.: acrocephaly, brachydactyly, prominent metopic ridge, broad depressed nasal bridge, narrow maxillae, obesity and normal intelligence. We discuss the relationship between this combination of clinical signs and symptoms most compatible with the diagnosis of Summitt syndrome and the Carpenter syndrome.

Utensil swab test: its effectiveness in food service sanitation programs.

The effectiveness of the utensil swab test as part of the periodic inspection of food establishments was studied both as an indicator of cleanliness during the period between inspections and as an educational tool. Two to seven samplings were taken at intervals of two to three months at 95 food establishments in rural areas in the northern part of Israel. A statistical analysis showed a high variation and almost no correlation between repeated samplings of the same establishment. Also, no trend to suggest an educational effect was found. We concluded that, though the swab test had proved to be useful in special projects, it had no value as part of the periodic sanitary inspections.

Edwardsiella tarda isolated in Israel between 1961 and 1980.

Edwardsiella tarda was isolated from patients, water tortoises (Clemmys caspica), and samples of water from Lake Kinnereth, the river Jordan, well water, and sewage water. Of the 53 isolates, 35 belonged to completely identified serotypes, among them 7 new ones. Fourteen cultures had O antigens, and one had an H antigen, different from those previously described. Three serotypes isolated from patients were also found in other sources: water tortoises, lake water, or both.

ICMSF Methods Studies. XV. Comparison of Four Media and Methods for Enumerating Staphylococcus aureus in Powdered Milk.

Four media were examined for their usefulness in enumerating Staphylococcus aureus inoculated (a) into milk that was then dried or (b) directly into dried milk powder. In all, seven strains of S. aureus were inoculated individually into each preparation and were enumerated after two periods of storage (18 to 19 d and 60 to 61 d). Fourteen laboratories from twelve countries participated in the comparison which found that direct plating on agar medium in 14-cm petri dishes may be as useful as enrichment followed by streaking. Plating on Baird-Parker medium or on Hauschild pork plasma fibrinogen medium and a MPN method using Giolitti and Cantoni's broth with Tween 80 were equally sensitive for enumerating S. aureus in dried milk powder. The use of Hauschild medium may eliminate the need for supplementary tests to confirm colonies as S. aureus , but in some cases was found to fail in some laboratories. Giolitti and Cantoni's broth without Tween 80 generally was less useful than the three other media for enumerating S. aureus . S. aureus inoculated into milk that was then dried survived longer than when inoculated into dried milk.